Electromagnetic Radiation - Revision history

Cmditradmin at 18:53, 23 July 2018

2018-07-23T18:53:54Z

← Older revision		Revision as of 11:53, 23 July 2018
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	A vibration at 1600 cm<sup>-1</sup> (~0.2eV) will be seen in the time domain as an oscillation with a period of ~20 fs.		A vibration at 1600 cm<sup>-1</sup> (~0.2eV) will be seen in the time domain as an oscillation with a period of ~20 fs.

	~~<iframe src="https://www.learnclick.com/quiz/frame/30933" frameborder="0" width="100%" height="500" scrolling="auto" name="Learnclick"></iframe>~~

	[[category:Light]]		[[category:Light]]

2018-07-23T18:52:38Z

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 A vibration at 1600 cm<sup>-1</sup> (~0.2eV) will be seen in the time domain as an oscillation with a period of ~20 fs.
-== Knowledge Check ==
+<iframe src="https://www.learnclick.com/quiz/frame/30933" frameborder="0" width="100%" height="500" scrolling="auto" name="Learnclick"></iframe>
 [[category:Light]]
 {{author

2010-08-19T22:01:46Z

← Older revision		Revision as of 15:01, 19 August 2010
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	</quiz>		</quiz>
	[[category:Light]]		[[category:Light]]
			{{author
			\|AuthorFullName= Bredas, Jean-Luc
			\|AuthorName=Bredas}}
	<table id="toc" style="width: 100%">		<table id="toc" style="width: 100%">
	<tr>		<tr>

2010-06-23T16:05:42Z

Visible spectrum

← Older revision		Revision as of 09:05, 23 June 2010
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	=== Visible spectrum ===		=== Visible spectrum ===

	[[Image:Visiblespectrum.jpg\|thumb\|~~300px~~\|The visible is a very small part of the electromagnetic spectrum, from 700nm on the low energy red side to 400nm on the high energy violet side]]		[[Image:Visiblespectrum.jpg\|thumb\|500px\|The visible is a very small part of the electromagnetic spectrum, from 700nm on the low energy red side to 400nm on the high energy violet side]]
	The energies of the spectrum vary from about 3eV on the violet side to 1.5eV on the red side in approximate terms. The frequencies are in the mid 10<sup>14</sup> scales. This is important because it determines the time scales for events. For example an event such as energy transition in a π conjugated system which will be 2 or 3eV, this is in the range of the visible spectra frequencies so the timescale for that process will be in the femptoseconds.		The energies of the spectrum vary from about 3eV on the violet side to 1.5eV on the red side in approximate terms. The frequencies are in the mid 10<sup>14</sup> scales. This is important because it determines the time scales for events. For example an event such as energy transition in a π conjugated system which will be 2 or 3eV, this is in the range of the visible spectra frequencies so the timescale for that process will be in the femptoseconds.

2010-06-23T15:50:46Z

The Electromagnetic Spectrum

← Older revision		Revision as of 08:50, 23 June 2010
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	== The Electromagnetic Spectrum ==		== The Electromagnetic Spectrum ==
	[[Image:~~Emspectrum_energy~~.jpg\|\|600px\|The wavelength, frequency and energy of the em spectrum.]]		[[Image:EM Spectrum3-new.jpg\|\|600px\|The wavelength, frequency and energy of the em spectrum.]]
	<br clear='all'>		<br clear='all'>
	In the ultraviolet photons have 3 to 30 eV energies, in the range of 100 to 1000 eV there are soft x-rays, and beyond that hard x-rays. The visible spectrum has wavelengths of a nanometer. But in the soft x-rays wavelengths are in the order of angstroms. This is why you can use the diffraction of soft x-rays to explore the crystal structure of molecules; the wavelength is in the approximate scale of that of atoms and bonds. Gamma rays are in the range of mega eV.		In the ultraviolet photons have 3 to 30 eV energies, in the range of 100 to 1000 eV there are soft x-rays, and beyond that hard x-rays. The visible spectrum has wavelengths of a nanometer. But in the soft x-rays wavelengths are in the order of angstroms. This is why you can use the diffraction of soft x-rays to explore the crystal structure of molecules; the wavelength is in the approximate scale of that of atoms and bonds. Gamma rays are in the range of mega eV.

2009-12-29T19:12:47Z

2009-12-22T22:56:52Z

Knowledge Check

2009-12-22T22:56:42Z

Knowledge Check

← Older revision		Revision as of 15:56, 22 December 2009
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	\|\| Not even close, gamma rays might do this at 10<sup>-6</sup> eV.		\|\| Not even close, gamma rays might do this at 10<sup>-6</sup> eV.

			</quiz>
	this		this

2009-12-22T22:55:50Z

← Older revision		Revision as of 15:55, 22 December 2009
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	\|\| Not even close, gamma rays might do this at 10<sup>-6</sup> eV.		\|\| Not even close, gamma rays might do this at 10<sup>-6</sup> eV.

			this

	<table id="toc" style="width: 100%">		<table id="toc" style="width: 100%">

2009-12-01T21:37:36Z

The Electromagnetic Spectrum

← Older revision		Revision as of 14:37, 1 December 2009
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	Try your hand at [http://concave.stc.arizona.edu/thepoint/Interactive/emsquiz.html The EM Quiz]		Try your hand at [http://concave.stc.arizona.edu/thepoint/Interactive/emsquiz.html The EM Quiz]

			Explore the [http://www.nanoed.org/concepts_apps/wavecalc/WaveCalc.html Wavelength Calculator Applet ]

	=== Visible spectrum ===		=== Visible spectrum ===